Impact of childhood vaccination on racial disparities in invasive Streptococcus pneumoniae infections

Abstract

Context: Historically, incidence of pneumococcal disease in the United States has been higher among blacks than among whites. Following recommendation of a new 7-valent pneumococcal conjugate vaccine for children in October 2000, the incidence of invasive pneumococcal disease has declined dramatically, but the impact of vaccination on racial disparities in incidence of pneumococcal disease is unknown.

Objective: To assess the effect of conjugate vaccine introduction on rates of pneumococcal disease among whites and blacks in the United States.

Design, setting, and patients: Analysis of data from the Active Bacterial Core Surveillance (ABCs)/Emerging Infections Program Network, an active, population-based surveillance system in 7 states. Patients were 15,923 persons with invasive pneumococcal disease occurring between January 1, 1998, and December 31, 2002.

Main outcome measures: Age- and race-specific pneumococcal disease incidence rates (cases per 100 000 persons), rate ratios, and rate differences.

Results: Between 1998 and 2002, annual incidence rates for invasive pneumococcal disease decreased from 19.0 to 12.1 cases per 100 000 among whites and from 54.9 to 26.5 among blacks. Due to these declines, 14,730 fewer cases occurred among whites and 8780 fewer cases occurred among blacks in the United States in 2002, compared with 2 prevaccine years, 1998 and 1999. Before vaccine introduction, incidence among blacks was 2.9 times higher than among whites (95% confidence interval [CI], 2.7-3.0); in 2002, the black-white rate ratio had been reduced to 2.2 (95% CI, 2.0-2.4). Incidence among black children younger than 2 years went from being 3.3 times higher (95% CI, 3.0-3.7) than among white children in the prevaccine period to 1.6 times higher (95% CI, 1.1-2.2) in 2002. By 2002, 74% of white children and 68% of black children aged 19 to 35 months in the 7 states had received at least 1 dose of pneumococcal conjugate vaccine; 43% of white and 39% of black children received 3 or more doses.

Conclusion: Although blacks remain at higher risk of invasive pneumococcal disease, introduction of childhood pneumococcal vaccination has reduced the racial disparity in incidence of pneumococcal disease.